We don't need to handle them separately. Instead, just let them
decompose/casefold to themselves.
Change-Id: I01c3f2c98ae4d84269586cec09f18239cbee0abb
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
(cherry picked from commit 5c26d2f1d3f5e4be3e196526bead29ecb139cf91)
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
There are cases where EXT4 is a bit too conservative sending barriers down to
the disk; there are cases where the transaction in progress is not the one
that sent the barrier (in other words: the fsync is for a file for which the
IO happened more time ago and all data was already sent to the disk).
For that case, a more performing tradeoff can be made on SSD devices (which
have the ability to flush their dram caches in a hurry on a power fail event)
where the barrier gets sent to the disk, but we don't need to wait for the
barrier to complete. Any consecutive IO will block on the barrier correctly.
Signed-off-by: Adam W. Willis <return.of.octobot@gmail.com>
(cherry picked from commit 74aa09a7751e438bd15b5cd73f611021b7239240)
(cherry picked from commit fa3bdf1a32cac074ff52403cb9ce18eb18c7f7d1)
[ Upstream commit 97e86631bccddfbbe0c13f9a9605cdef11d31296 ]
In 196d59ab9ccc "btrfs: switch extent buffer tree lock to rw_semaphore"
the functions for tree read locking were rewritten, and in the process
the read lock functions started setting eb->lock_owner = current->pid.
Previously lock_owner was only set in tree write lock functions.
Read locks are shared, so they don't have exclusive ownership of the
underlying object, so setting lock_owner to any single value for a
read lock makes no sense. It's mostly harmless because write locks
and read locks are mutually exclusive, and none of the existing code
in btrfs (btrfs_init_new_buffer and print_eb_refs_lock) cares what
nonsense is written in lock_owner when no writer is holding the lock.
KCSAN does care, and will complain about the data race incessantly.
Remove the assignments in the read lock functions because they're
useless noise.
Fixes: 196d59ab9ccc ("btrfs: switch extent buffer tree lock to rw_semaphore")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4048daedb910f83f080c6bb03c78af794aebdff5 ]
Now that we're no longer using recursion, rip out all of the supporting
code. Follow up patches will clean up the callers of these functions.
The extent_buffer::lock_owner is still retained as it allows safety
checks in btrfs_init_new_buffer for the case that the free space cache
is corrupted and we try to allocate a block that we are currently using
and have locked in the path.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 97e86631bccd ("btrfs: don't set lock_owner when locking extent buffer for reading")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 44f52bbe96dfdbe4aca3818a2534520082a07040 ]
When a COWing a tree block, at btrfs_cow_block(), and we have the
tracepoint trace_btrfs_cow_block() enabled and preemption is also enabled
(CONFIG_PREEMPT=y), we can trigger a use-after-free in the COWed extent
buffer while inside the tracepoint code. This is because in some paths
that call btrfs_cow_block(), such as btrfs_search_slot(), we are holding
the last reference on the extent buffer @buf so btrfs_force_cow_block()
drops the last reference on the @buf extent buffer when it calls
free_extent_buffer_stale(buf), which schedules the release of the extent
buffer with RCU. This means that if we are on a kernel with preemption,
the current task may be preempted before calling trace_btrfs_cow_block()
and the extent buffer already released by the time trace_btrfs_cow_block()
is called, resulting in a use-after-free.
Fix this by moving the trace_btrfs_cow_block() from btrfs_cow_block() to
btrfs_force_cow_block() before the COWed extent buffer is freed.
This also has a side effect of invoking the tracepoint in the tree defrag
code, at defrag.c:btrfs_realloc_node(), since btrfs_force_cow_block() is
called there, but this is fine and it was actually missing there.
Reported-by: syzbot+8517da8635307182c8a5@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/6759a9b9.050a0220.1ac542.000d.GAE@google.com/
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 95f93bc4cbcac6121a5ee85cd5019ee8e7447e0b ]
Rename and export __btrfs_cow_block() as btrfs_force_cow_block(). This is
to allow to move defrag specific code out of ctree.c and into defrag.c in
one of the next patches.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 44f52bbe96df ("btrfs: fix use-after-free when COWing tree bock and tracing is enabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ac5887c8e013d6754d36e6d51dc03448ee0b0065 ]
Now that we're using a rw_semaphore we no longer need to indicate if a
lock is blocking or not, nor do we need to flip the entire path from
blocking to spinning. Remove these helpers and all the places they are
called.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 44f52bbe96df ("btrfs: fix use-after-free when COWing tree bock and tracing is enabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 196d59ab9ccc975d8d29292845d227cdf4423ef8 ]
Historically we've implemented our own locking because we wanted to be
able to selectively spin or sleep based on what we were doing in the
tree. For instance, if all of our nodes were in cache then there's
rarely a reason to need to sleep waiting for node locks, as they'll
likely become available soon. At the time this code was written the
rw_semaphore didn't do adaptive spinning, and thus was orders of
magnitude slower than our home grown locking.
However now the opposite is the case. There are a few problems with how
we implement blocking locks, namely that we use a normal waitqueue and
simply wake everybody up in reverse sleep order. This leads to some
suboptimal performance behavior, and a lot of context switches in highly
contended cases. The rw_semaphores actually do this properly, and also
have adaptive spinning that works relatively well.
The locking code is also a bit of a bear to understand, and we lose the
benefit of lockdep for the most part because the blocking states of the
lock are simply ad-hoc and not mapped into lockdep.
So rework the locking code to drop all of this custom locking stuff, and
simply use a rw_semaphore for everything. This makes the locking much
simpler for everything, as we can now drop a lot of cruft and blocking
transitions. The performance numbers vary depending on the workload,
because generally speaking there doesn't tend to be a lot of contention
on the btree. However, on my test system which is an 80 core single
socket system with 256GiB of RAM and a 2TiB NVMe drive I get the
following results (with all debug options off):
dbench 200 baseline
Throughput 216.056 MB/sec 200 clients 200 procs max_latency=1471.197 ms
dbench 200 with patch
Throughput 737.188 MB/sec 200 clients 200 procs max_latency=714.346 ms
Previously we also used fs_mark to test this sort of contention, and
those results are far less impressive, mostly because there's not enough
tasks to really stress the locking
fs_mark -d /d[0-15] -S 0 -L 20 -n 100000 -s 0 -t 16
baseline
Average Files/sec: 160166.7
p50 Files/sec: 165832
p90 Files/sec: 123886
p99 Files/sec: 123495
real 3m26.527s
user 2m19.223s
sys 48m21.856s
patched
Average Files/sec: 164135.7
p50 Files/sec: 171095
p90 Files/sec: 122889
p99 Files/sec: 113819
real 3m29.660s
user 2m19.990s
sys 44m12.259s
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 44f52bbe96df ("btrfs: fix use-after-free when COWing tree bock and tracing is enabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit d5ff2fb2e7167e9483846e34148e60c0c016a1f6 upstream.
In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the
function `nfs4_state_destroy_net` in `nfs4_state_shutdown_net` will
release all resources related to the hashed `nfs4_client`. If the
`nfsd_client_shrinker` is running concurrently, the `expire_client`
function will first unhash this client and then destroy it. This can
lead to the following warning. Additionally, numerous use-after-free
errors may occur as well.
nfsd_client_shrinker echo 0 > /proc/fs/nfsd/threads
expire_client nfsd_shutdown_net
unhash_client ...
nfs4_state_shutdown_net
/* won't wait shrinker exit */
/* cancel_work(&nn->nfsd_shrinker_work)
* nfsd_file for this /* won't destroy unhashed client1 */
* client1 still alive nfs4_state_destroy_net
*/
nfsd_file_cache_shutdown
/* trigger warning */
kmem_cache_destroy(nfsd_file_slab)
kmem_cache_destroy(nfsd_file_mark_slab)
/* release nfsd_file and mark */
__destroy_client
====================================================================
BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on
__kmem_cache_shutdown()
--------------------------------------------------------------------
CPU: 4 UID: 0 PID: 764 Comm: sh Not tainted 6.12.0-rc3+ #1
dump_stack_lvl+0x53/0x70
slab_err+0xb0/0xf0
__kmem_cache_shutdown+0x15c/0x310
kmem_cache_destroy+0x66/0x160
nfsd_file_cache_shutdown+0xac/0x210 [nfsd]
nfsd_destroy_serv+0x251/0x2a0 [nfsd]
nfsd_svc+0x125/0x1e0 [nfsd]
write_threads+0x16a/0x2a0 [nfsd]
nfsctl_transaction_write+0x74/0xa0 [nfsd]
vfs_write+0x1a5/0x6d0
ksys_write+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
====================================================================
BUG nfsd_file_mark (Tainted: G B W ): Objects remaining
nfsd_file_mark on __kmem_cache_shutdown()
--------------------------------------------------------------------
dump_stack_lvl+0x53/0x70
slab_err+0xb0/0xf0
__kmem_cache_shutdown+0x15c/0x310
kmem_cache_destroy+0x66/0x160
nfsd_file_cache_shutdown+0xc8/0x210 [nfsd]
nfsd_destroy_serv+0x251/0x2a0 [nfsd]
nfsd_svc+0x125/0x1e0 [nfsd]
write_threads+0x16a/0x2a0 [nfsd]
nfsctl_transaction_write+0x74/0xa0 [nfsd]
vfs_write+0x1a5/0x6d0
ksys_write+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
To resolve this issue, cancel `nfsd_shrinker_work` using synchronous
mode in nfs4_state_shutdown_net.
Fixes: 7c24fa225081 ("NFSD: replace delayed_work with work_struct for nfsd_client_shrinker")
Signed-off-by: Yang Erkun <yangerkun@huaweicloud.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2c8507c63f5498d4ee4af404a8e44ceae4345056 upstream.
During swap activation we iterate over the extents of a file and we can
have many thousands of them, so we can end up in a busy loop monopolizing
a core. Avoid this by doing a voluntary reschedule after processing each
extent.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7917f01a286ce01e9c085e24468421f596ee1a0c ]
A recent patch inadvertently broke callbacks for NFSv4.0.
In the 4.0 case we do not expect a session to be found but still need to
call setup_callback_client() which will not try to dereference it.
This patch moves the check for failure to find a session into the 4.1+
branch of setup_callback_client()
Fixes: 1e02c641c3a4 ("NFSD: Prevent NULL dereference in nfsd4_process_cb_update()")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 900bbaae67e980945dec74d36f8afe0de7556d5a upstream.
Now, the epoll only use wake_up() interface to wake up task.
However, sometimes, there are epoll users which want to use
the synchronous wakeup flag to hint the scheduler, such as
Android binder driver.
So add a wake_up_sync() define, and use the wake_up_sync()
when the sync is true in ep_poll_callback().
Co-developed-by: Jing Xia <jing.xia@unisoc.com>
Signed-off-by: Jing Xia <jing.xia@unisoc.com>
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Link: https://lore.kernel.org/r/20240426080548.8203-1-xuewen.yan@unisoc.com
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Reported-by: Benoit Lize <lizeb@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 12eb22a5a609421b380c3c6ca887474fb2089b2c upstream.
It becomes a path component, so it shouldn't exceed NAME_MAX
characters. This was hardened in commit c152737be22b ("ceph: Use
strscpy() instead of strcpy() in __get_snap_name()"), but no actual
check was put in place.
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 62e2a47ceab8f3f7d2e3f0e03fdd1c5e0059fd8b upstream.
When the server is recalling a layout, we should ignore the count of
outstanding layoutget calls, since the server is expected to return
either NFS4ERR_RECALLCONFLICT or NFS4ERR_RETURNCONFLICT for as long as
the recall is outstanding.
Currently, we may end up livelocking, causing the layout to eventually
be forcibly revoked.
Fixes: bf0291dd2267 ("pNFS: Ensure LAYOUTGET and LAYOUTRETURN are properly serialised")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dfb92681a19e1d5172420baa242806414b3eff6f upstream.
[BUG]
There is a bug report in the mailing list where btrfs_run_delayed_refs()
failed to drop the ref count for logical 25870311358464 num_bytes
2113536.
The involved leaf dump looks like this:
item 166 key (25870311358464 168 2113536) itemoff 10091 itemsize 50
extent refs 1 gen 84178 flags 1
ref#0: shared data backref parent 32399126528000 count 0 <<<
ref#1: shared data backref parent 31808973717504 count 1
Notice the count number is 0.
[CAUSE]
There is no concrete evidence yet, but considering 0 -> 1 is also a
single bit flipped, it's possible that hardware memory bitflip is
involved, causing the on-disk extent tree to be corrupted.
[FIX]
To prevent us reading such corrupted extent item, or writing such
damaged extent item back to disk, enhance the handling of
BTRFS_EXTENT_DATA_REF_KEY and BTRFS_SHARED_DATA_REF_KEY keys for both
inlined and key items, to detect such 0 ref count and reject them.
CC: stable@vger.kernel.org # 5.4+
Link: https://lore.kernel.org/linux-btrfs/7c69dd49-c346-4806-86e7-e6f863a66f48@app.fastmail.com/
Reported-by: Frankie Fisher <frankie@terrorise.me.uk>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2ab0837cb91b7de507daa145d17b3b6b2efb3abf upstream.
When looking up a non-existent file, efivarfs returns -EINVAL if the
file does not conform to the NAME-GUID format and -ENOENT if it does.
This is caused by efivars_d_hash() returning -EINVAL if the name is not
formatted correctly. This error is returned before simple_lookup()
returns a negative dentry, and is the error value that the user sees.
Fix by removing this check. If the file does not exist, simple_lookup()
will return a negative dentry leading to -ENOENT and efivarfs_create()
already has a validity check before it creates an entry (and will
correctly return -EINVAL)
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: <stable@vger.kernel.org>
[ardb: make efivarfs_valid_name() static]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9ed50b8231e37b1ae863f5dec8153b98d9f389b4 upstream.
Fast symlink can be used if the on-disk symlink data is stored
in the same block as the on-disk inode, so we don’t need to trigger
another I/O for symlink data. However, currently fs correction could be
reported _incorrectly_ if inode xattrs are too large.
In fact, these should be valid images although they cannot be handled as
fast symlinks.
Many thanks to Colin for reporting this!
Reported-by: Colin Walters <walters@verbum.org>
Reported-by: https://honggfuzz.dev/
Link: https://lore.kernel.org/r/bb2dd430-7de0-47da-ae5b-82ab2dd4d945@app.fastmail.com
Fixes: 431339ba9042 ("staging: erofs: add inode operations")
[ Note that it's a runtime misbehavior instead of a security issue. ]
Link: https://lore.kernel.org/r/20240909031911.1174718-1-hsiangkao@linux.alibaba.com
[ Gao Xiang: fix 5.10.y build warning due to `check_add_overflow`. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 89fc548767a2155231128cb98726d6d2ea1256c9 upstream.
When accessing a file with more entries than ES_MAX_ENTRY_NUM, the bh-array
is allocated in __exfat_get_entry_set. The problem is that the bh-array is
allocated with GFP_KERNEL. It does not make sense. In the following cases,
a deadlock for sbi->s_lock between the two processes may occur.
CPU0 CPU1
---- ----
kswapd
balance_pgdat
lock(fs_reclaim)
exfat_iterate
lock(&sbi->s_lock)
exfat_readdir
exfat_get_uniname_from_ext_entry
exfat_get_dentry_set
__exfat_get_dentry_set
kmalloc_array
...
lock(fs_reclaim)
...
evict
exfat_evict_inode
lock(&sbi->s_lock)
To fix this, let's allocate bh-array with GFP_NOFS.
Fixes: a3ff29a95fde ("exfat: support dynamic allocate bh for exfat_entry_set_cache")
Cc: stable@vger.kernel.org # v6.2+
Reported-by: syzbot+412a392a2cd4a65e71db@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/000000000000fef47e0618c0327f@google.com
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
[Sherry: The problematic commit was backported to 5.15.y and 5.10.y, thus backport this fix]
Signed-off-by: Sherry Yang <sherry.yang@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ffc3ea4f3c1cc83a86b7497b0c4b0aee7de5480d upstream.
Fix a minor mistakes in the scrub tracepoints that can manifest when
inode-rooted btrees are enabled. The existing code worked fine for bmap
btrees, but we should tighten the code up to be less sloppy.
Cc: <stable@vger.kernel.org> # v5.7
Fixes: 92219c292af8dd ("xfs: convert btree cursor inode-private member names")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7ce31f20a0771d71779c3b0ec9cdf474cc3c8e9a upstream.
Way back when we first implemented FICLONE for XFS, life was simple --
either the the entire remapping completed, or something happened and we
had to return an errno explaining what happened. Neither of those
ioctls support returning partial results, so it's all or nothing.
Then things got complicated when copy_file_range came along, because it
actually can return the number of bytes copied, so commit 3f68c1f562f1e4
tried to make it so that we could return a partial result if the
REMAP_FILE_CAN_SHORTEN flag is set. This is also how FIDEDUPERANGE can
indicate that the kernel performed a partial deduplication.
Unfortunately, the logic is wrong if an error stops the remapping and
CAN_SHORTEN is not set. Because those callers cannot return partial
results, it is an error for ->remap_file_range to return a positive
quantity that is less than the @len passed in. Implementations really
should be returning a negative errno in this case, because that's what
btrfs (which introduced FICLONE{,RANGE}) did.
Therefore, ->remap_range implementations cannot silently drop an errno
that they might have when the number of bytes remapped is less than the
number of bytes requested and CAN_SHORTEN is not set.
Found by running generic/562 on a 64k fsblock filesystem and wondering
why it reported corrupt files.
Cc: <stable@vger.kernel.org> # v4.20
Fixes: 3fc9f5e409319e ("xfs: remove xfs_reflink_remap_range")
Really-Fixes: 3f68c1f562f1e4 ("xfs: support returning partial reflink results")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All callers of d_alloc_parallel() must make sure that resulting
in-lookup dentry (if any) will encounter __d_lookup_done() before
the final dput(). d_add_ci() might end up creating in-lookup
dentries; they are fed to d_splice_alias(), which will normally
make sure they meet __d_lookup_done(). However, it is possible
to end up with d_splice_alias() failing with ERR_PTR(-ELOOP)
without having done so. It takes a corrupted ntfs or case-insensitive
xfs image, but neither should end up with memory corruption...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
commit b29bf7119d6bbfd04aabb8d82b060fe2a33ef890 upstream.
The fix for a memory corruption contained a off-by-one error and
caused the compressor to fail in legit cases.
Cc: Kinsey Moore <kinsey.moore@oarcorp.com>
Cc: stable@vger.kernel.org
Fixes: fe051552f5078 ("jffs2: Prevent rtime decompress memory corruption")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fe051552f5078fa02d593847529a3884305a6ffe upstream.
The rtime decompression routine does not fully check bounds during the
entirety of the decompression pass and can corrupt memory outside the
decompression buffer if the compressed data is corrupted. This adds the
required check to prevent this failure mode.
Cc: stable@vger.kernel.org
Signed-off-by: Kinsey Moore <kinsey.moore@oarcorp.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9c803c474c6c002d8ade68ebe99026cc39c37f85 ]
When activating a swap file we acquire the root's snapshot drew lock and
then check if the root is dead, failing and returning with -EPERM if it's
dead but without unlocking the root's snapshot lock. Fix this by adding
the missing unlock.
Fixes: 60021bd754c6 ("btrfs: prevent subvol with swapfile from being deleted")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d5c367ef8287fb4d235c46a2f8c8d68715f3a0ca ]
creating a large files during checkpoint disable until it runs out of
space and then delete it, then remount to enable checkpoint again, and
then unmount the filesystem triggers the f2fs_bug_on as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/inode.c:896!
CPU: 2 UID: 0 PID: 1286 Comm: umount Not tainted 6.11.0-rc7-dirty #360
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:f2fs_evict_inode+0x58c/0x610
Call Trace:
__die_body+0x15/0x60
die+0x33/0x50
do_trap+0x10a/0x120
f2fs_evict_inode+0x58c/0x610
do_error_trap+0x60/0x80
f2fs_evict_inode+0x58c/0x610
exc_invalid_op+0x53/0x60
f2fs_evict_inode+0x58c/0x610
asm_exc_invalid_op+0x16/0x20
f2fs_evict_inode+0x58c/0x610
evict+0x101/0x260
dispose_list+0x30/0x50
evict_inodes+0x140/0x190
generic_shutdown_super+0x2f/0x150
kill_block_super+0x11/0x40
kill_f2fs_super+0x7d/0x140
deactivate_locked_super+0x2a/0x70
cleanup_mnt+0xb3/0x140
task_work_run+0x61/0x90
The root cause is: creating large files during disable checkpoint
period results in not enough free segments, so when writing back root
inode will failed in f2fs_enable_checkpoint. When umount the file
system after enabling checkpoint, the root inode is dirty in
f2fs_evict_inode function, which triggers BUG_ON. The steps to
reproduce are as follows:
dd if=/dev/zero of=f2fs.img bs=1M count=55
mount f2fs.img f2fs_dir -o checkpoint=disable:10%
dd if=/dev/zero of=big bs=1M count=50
sync
rm big
mount -o remount,checkpoint=enable f2fs_dir
umount f2fs_dir
Let's redirty inode when there is not free segments during checkpoint
is disable.
Signed-off-by: Qi Han <hanqi@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a5f5e4698f8abbb25fe4959814093fb5bfa1aa9d ]
When dmt_budmin is less than zero, it causes errors
in the later stages. Added a check to return an error beforehand
in dbAllocCtl itself.
Reported-by: syzbot+b5ca8a249162c4b9a7d0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b5ca8a249162c4b9a7d0
Signed-off-by: Ghanshyam Agrawal <ghanshyam1898@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ca84a2c9be482836b86d780244f0357e5a778c46 ]
The value of stbl can be sometimes out of bounds due
to a bad filesystem. Added a check with appopriate return
of error code in that case.
Reported-by: syzbot+65fa06e29859e41a83f3@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=65fa06e29859e41a83f3
Signed-off-by: Ghanshyam Agrawal <ghanshyam1898@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2e8b6bc0ab41ce41e6dfcc204b6cc01d5abbc952 ]
[PROBLEM]
It is very common for udev to trigger device scan, and every time a
mounted btrfs device got re-scan from different soft links, we will get
some of unnecessary device path updates, this is especially common
for LVM based storage:
# lvs
scratch1 test -wi-ao---- 10.00g
scratch2 test -wi-a----- 10.00g
scratch3 test -wi-a----- 10.00g
scratch4 test -wi-a----- 10.00g
scratch5 test -wi-a----- 10.00g
test test -wi-a----- 10.00g
# mkfs.btrfs -f /dev/test/scratch1
# mount /dev/test/scratch1 /mnt/btrfs
# dmesg -c
[ 205.705234] BTRFS: device fsid 7be2602f-9e35-4ecf-a6ff-9e91d2c182c9 devid 1 transid 6 /dev/mapper/test-scratch1 (253:4) scanned by mount (1154)
[ 205.710864] BTRFS info (device dm-4): first mount of filesystem 7be2602f-9e35-4ecf-a6ff-9e91d2c182c9
[ 205.711923] BTRFS info (device dm-4): using crc32c (crc32c-intel) checksum algorithm
[ 205.713856] BTRFS info (device dm-4): using free-space-tree
[ 205.722324] BTRFS info (device dm-4): checking UUID tree
So far so good, but even if we just touched any soft link of
"dm-4", we will get quite some unnecessary device path updates.
# touch /dev/mapper/test-scratch1
# dmesg -c
[ 469.295796] BTRFS info: devid 1 device path /dev/mapper/test-scratch1 changed to /dev/dm-4 scanned by (udev-worker) (1221)
[ 469.300494] BTRFS info: devid 1 device path /dev/dm-4 changed to /dev/mapper/test-scratch1 scanned by (udev-worker) (1221)
Such device path rename is unnecessary and can lead to random path
change due to the udev race.
[CAUSE]
Inside device_list_add(), we are using a very primitive way checking if
the device has changed, strcmp().
Which can never handle links well, no matter if it's hard or soft links.
So every different link of the same device will be treated as a different
device, causing the unnecessary device path update.
[FIX]
Introduce a helper, is_same_device(), and use path_equal() to properly
detect the same block device.
So that the different soft links won't trigger the rename race.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Link: https://bugzilla.suse.com/show_bug.cgi?id=1230641
Reported-by: Fabian Vogt <fvogt@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 914eec5e980171bc128e7e24f7a22aa1d803570e upstream.
The following INFO level message was seen:
seq_file: buggy .next function ocfs2_dlm_seq_next [ocfs2] did not
update position index
Fix:
Update *pos (so m->index) to make seq_read_iter happy though the index its
self makes no sense to ocfs2_dlm_seq_next.
Link: https://lkml.kernel.org/r/20241119174500.9198-1-wen.gang.wang@oracle.com
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 985ebec4ab0a28bb5910c3b1481a40fbf7f9e61d upstream.
Syzbot reported that when searching for records in a directory where the
inode's i_size is corrupted and has a large value, memory access outside
the folio/page range may occur, or a use-after-free bug may be detected if
KASAN is enabled.
This is because nilfs_last_byte(), which is called by nilfs_find_entry()
and others to calculate the number of valid bytes of directory data in a
page from i_size and the page index, loses the upper 32 bits of the 64-bit
size information due to an inappropriate type of local variable to which
the i_size value is assigned.
This caused a large byte offset value due to underflow in the end address
calculation in the calling nilfs_find_entry(), resulting in memory access
that exceeds the folio/page size.
Fix this issue by changing the type of the local variable causing the bit
loss from "unsigned int" to "u64". The return value of nilfs_last_byte()
is also of type "unsigned int", but it is truncated so as not to exceed
PAGE_SIZE and no bit loss occurs, so no change is required.
Link: https://lkml.kernel.org/r/20241119172403.9292-1-konishi.ryusuke@gmail.com
Fixes: 2ba466d74ed7 ("nilfs2: directory entry operations")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+96d5d14c47d97015c624@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=96d5d14c47d97015c624
Tested-by: syzbot+96d5d14c47d97015c624@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 98100e88dd8865999dc6379a3356cd799795fe7b upstream.
The action force umount(umount -f) will attempt to kill all rpc_task even
umount operation may ultimately fail if some files remain open.
Consequently, if an action attempts to open a file, it can potentially
send two rpc_task to nfs server.
NFS CLIENT
thread1 thread2
open("file")
...
nfs4_do_open
_nfs4_do_open
_nfs4_open_and_get_state
_nfs4_proc_open
nfs4_run_open_task
/* rpc_task1 */
rpc_run_task
rpc_wait_for_completion_task
umount -f
nfs_umount_begin
rpc_killall_tasks
rpc_signal_task
rpc_task1 been wakeup
and return -512
_nfs4_do_open // while loop
...
nfs4_run_open_task
/* rpc_task2 */
rpc_run_task
rpc_wait_for_completion_task
While processing an open request, nfsd will first attempt to find or
allocate an nfs4_openowner. If it finds an nfs4_openowner that is not
marked as NFS4_OO_CONFIRMED, this nfs4_openowner will released. Since
two rpc_task can attempt to open the same file simultaneously from the
client to server, and because two instances of nfsd can run
concurrently, this situation can lead to lots of memory leak.
Additionally, when we echo 0 to /proc/fs/nfsd/threads, warning will be
triggered.
NFS SERVER
nfsd1 nfsd2 echo 0 > /proc/fs/nfsd/threads
nfsd4_open
nfsd4_process_open1
find_or_alloc_open_stateowner
// alloc oo1, stateid1
nfsd4_open
nfsd4_process_open1
find_or_alloc_open_stateowner
// find oo1, without NFS4_OO_CONFIRMED
release_openowner
unhash_openowner_locked
list_del_init(&oo->oo_perclient)
// cannot find this oo
// from client, LEAK!!!
alloc_stateowner // alloc oo2
nfsd4_process_open2
init_open_stateid
// associate oo1
// with stateid1, stateid1 LEAK!!!
nfs4_get_vfs_file
// alloc nfsd_file1 and nfsd_file_mark1
// all LEAK!!!
nfsd4_process_open2
...
write_threads
...
nfsd_destroy_serv
nfsd_shutdown_net
nfs4_state_shutdown_net
nfs4_state_destroy_net
destroy_client
__destroy_client
// won't find oo1!!!
nfsd_shutdown_generic
nfsd_file_cache_shutdown
kmem_cache_destroy
for nfsd_file_slab
and nfsd_file_mark_slab
// bark since nfsd_file1
// and nfsd_file_mark1
// still alive
=======================================================================
BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on
__kmem_cache_shutdown()
-----------------------------------------------------------------------
Slab 0xffd4000004438a80 objects=34 used=1 fp=0xff11000110e2ad28
flags=0x17ffffc0000240(workingset|head|node=0|zone=2|lastcpupid=0x1fffff)
CPU: 4 UID: 0 PID: 757 Comm: sh Not tainted 6.12.0-rc6+ #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x53/0x70
slab_err+0xb0/0xf0
__kmem_cache_shutdown+0x15c/0x310
kmem_cache_destroy+0x66/0x160
nfsd_file_cache_shutdown+0xac/0x210 [nfsd]
nfsd_destroy_serv+0x251/0x2a0 [nfsd]
nfsd_svc+0x125/0x1e0 [nfsd]
write_threads+0x16a/0x2a0 [nfsd]
nfsctl_transaction_write+0x74/0xa0 [nfsd]
vfs_write+0x1ae/0x6d0
ksys_write+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Disabling lock debugging due to kernel taint
Object 0xff11000110e2ac38 @offset=3128
Allocated in nfsd_file_do_acquire+0x20f/0xa30 [nfsd] age=1635 cpu=3
pid=800
nfsd_file_do_acquire+0x20f/0xa30 [nfsd]
nfsd_file_acquire_opened+0x5f/0x90 [nfsd]
nfs4_get_vfs_file+0x4c9/0x570 [nfsd]
nfsd4_process_open2+0x713/0x1070 [nfsd]
nfsd4_open+0x74b/0x8b0 [nfsd]
nfsd4_proc_compound+0x70b/0xc20 [nfsd]
nfsd_dispatch+0x1b4/0x3a0 [nfsd]
svc_process_common+0x5b8/0xc50 [sunrpc]
svc_process+0x2ab/0x3b0 [sunrpc]
svc_handle_xprt+0x681/0xa20 [sunrpc]
nfsd+0x183/0x220 [nfsd]
kthread+0x199/0x1e0
ret_from_fork+0x31/0x60
ret_from_fork_asm+0x1a/0x30
Add nfs4_openowner_unhashed to help found unhashed nfs4_openowner, and
break nfsd4_open process to fix this problem.
Cc: stable@vger.kernel.org # v5.4+
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit be8f982c369c965faffa198b46060f8853e0f1f0 upstream.
The function `e_show` was called with protection from RCU. This only
ensures that `exp` will not be freed. Therefore, the reference count for
`exp` can drop to zero, which will trigger a refcount use-after-free
warning when `exp_get` is called. To resolve this issue, use
`cache_get_rcu` to ensure that `exp` remains active.
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 819 at lib/refcount.c:25
refcount_warn_saturate+0xb1/0x120
CPU: 3 UID: 0 PID: 819 Comm: cat Not tainted 6.12.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb1/0x120
...
Call Trace:
<TASK>
e_show+0x20b/0x230 [nfsd]
seq_read_iter+0x589/0x770
seq_read+0x1e5/0x270
vfs_read+0x125/0x530
ksys_read+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Fixes: bf18f163e89c ("NFSD: Using exp_get for export getting")
Cc: stable@vger.kernel.org # 4.20+
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ac6f420291b3fee1113f21d612fa88b628afab5b ]
One of the paths quota writeback is called from is:
freeze_super()
sync_filesystem()
ext4_sync_fs()
dquot_writeback_dquots()
Since we currently don't always flush the quota_release_work queue in
this path, we can end up with the following race:
1. dquot are added to releasing_dquots list during regular operations.
2. FS Freeze starts, however, this does not flush the quota_release_work queue.
3. Freeze completes.
4. Kernel eventually tries to flush the workqueue while FS is frozen which
hits a WARN_ON since transaction gets started during frozen state:
ext4_journal_check_start+0x28/0x110 [ext4] (unreliable)
__ext4_journal_start_sb+0x64/0x1c0 [ext4]
ext4_release_dquot+0x90/0x1d0 [ext4]
quota_release_workfn+0x43c/0x4d0
Which is the following line:
WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
Which ultimately results in generic/390 failing due to dmesg
noise. This was detected on powerpc machine 15 cores.
To avoid this, make sure to flush the workqueue during
dquot_writeback_dquots() so we dont have any pending workitems after
freeze.
Reported-by: Disha Goel <disgoel@linux.ibm.com>
CC: stable@vger.kernel.org
Fixes: dabc8b207566 ("quota: fix dqput() to follow the guarantees dquot_srcu should provide")
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20241121123855.645335-2-ojaswin@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 52cb7f8f177878b4f22397b9c4d2c8f743766be3 ]
When exporting only one file system with fsid=0 on the server side, the
client alternately uses the ro/rw mount options to perform the mount
operation, and a new vfsmount is generated each time.
It can be reproduced as follows:
[root@localhost ~]# mount /dev/sda /mnt2
[root@localhost ~]# echo "/mnt2 *(rw,no_root_squash,fsid=0)" >/etc/exports
[root@localhost ~]# systemctl restart nfs-server
[root@localhost ~]# mount -t nfs -o ro,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount -t nfs -o rw,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount -t nfs -o ro,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount -t nfs -o rw,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount | grep nfs4
127.0.0.1:/ on /mnt/sdaa type nfs4 (ro,relatime,vers=4.2,rsize=1048576,...
127.0.0.1:/ on /mnt/sdaa type nfs4 (rw,relatime,vers=4.2,rsize=1048576,...
127.0.0.1:/ on /mnt/sdaa type nfs4 (ro,relatime,vers=4.2,rsize=1048576,...
127.0.0.1:/ on /mnt/sdaa type nfs4 (rw,relatime,vers=4.2,rsize=1048576,...
[root@localhost ~]#
We expected that after mounting with the ro option, using the rw option to
mount again would return EBUSY, but the actual situation was not the case.
As shown above, when mounting for the first time, a superblock with the ro
flag will be generated, and at the same time, in do_new_mount_fc -->
do_add_mount, it detects that the superblock corresponding to the current
target directory is inconsistent with the currently generated one
(path->mnt->mnt_sb != newmnt->mnt.mnt_sb), and a new vfsmount will be
generated.
When mounting with the rw option for the second time, since no matching
superblock can be found in the fs_supers list, a new superblock with the
rw flag will be generated again. The superblock in use (ro) is different
from the newly generated superblock (rw), and a new vfsmount will be
generated again.
When mounting with the ro option for the third time, the superblock (ro)
is found in fs_supers, the superblock in use (rw) is different from the
found superblock (ro), and a new vfsmount will be generated again.
We can switch between ro/rw through remount, and only one superblock needs
to be generated, thus avoiding the problem of repeated generation of
vfsmount caused by switching superblocks.
Furthermore, This can also resolve the issue described in the link.
Fixes: 275a5d24bf56 ("NFS: Error when mounting the same filesystem with different options")
Link: https://lore.kernel.org/all/20240604112636.236517-3-lilingfeng@huaweicloud.com/
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3ba44ee966bc3c41dd8a944f963466c8fcc60dc8 ]
When building the kernel with -Wmaybe-uninitialized, the compiler
reports this warning:
In function 'jffs2_mark_erased_block',
inlined from 'jffs2_erase_pending_blocks' at fs/jffs2/erase.c:116:4:
fs/jffs2/erase.c:474:9: warning: 'bad_offset' may be used uninitialized [-Wmaybe-uninitialized]
474 | jffs2_erase_failed(c, jeb, bad_offset);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/jffs2/erase.c: In function 'jffs2_erase_pending_blocks':
fs/jffs2/erase.c:402:18: note: 'bad_offset' was declared here
402 | uint32_t bad_offset;
| ^~~~~~~~~~
When mtd->point() is used, jffs2_erase_pending_blocks can return -EIO
without initializing bad_offset, which is later used at the filebad
label in jffs2_mark_erased_block.
Fix it by initializing this variable.
Fixes: 8a0f572397ca ("[JFFS2] Return values of jffs2_block_check_erase error paths")
Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4617fb8fc15effe8eda4dd898d4e33eb537a7140 ]
After an insertion in TNC, the tree might split and cause a node to
change its `znode->parent`. A further deletion of other nodes in the
tree (which also could free the nodes), the aforementioned node's
`znode->cparent` could still point to a freed node. This
`znode->cparent` may not be updated when getting nodes to commit in
`ubifs_tnc_start_commit()`. This could then trigger a use-after-free
when accessing the `znode->cparent` in `write_index()` in
`ubifs_tnc_end_commit()`.
This can be triggered by running
rm -f /etc/test-file.bin
dd if=/dev/urandom of=/etc/test-file.bin bs=1M count=60 conv=fsync
in a loop, and with `CONFIG_UBIFS_FS_AUTHENTICATION`. KASAN then
reports:
BUG: KASAN: use-after-free in ubifs_tnc_end_commit+0xa5c/0x1950
Write of size 32 at addr ffffff800a3af86c by task ubifs_bgt0_20/153
Call trace:
dump_backtrace+0x0/0x340
show_stack+0x18/0x24
dump_stack_lvl+0x9c/0xbc
print_address_description.constprop.0+0x74/0x2b0
kasan_report+0x1d8/0x1f0
kasan_check_range+0xf8/0x1a0
memcpy+0x84/0xf4
ubifs_tnc_end_commit+0xa5c/0x1950
do_commit+0x4e0/0x1340
ubifs_bg_thread+0x234/0x2e0
kthread+0x36c/0x410
ret_from_fork+0x10/0x20
Allocated by task 401:
kasan_save_stack+0x38/0x70
__kasan_kmalloc+0x8c/0xd0
__kmalloc+0x34c/0x5bc
tnc_insert+0x140/0x16a4
ubifs_tnc_add+0x370/0x52c
ubifs_jnl_write_data+0x5d8/0x870
do_writepage+0x36c/0x510
ubifs_writepage+0x190/0x4dc
__writepage+0x58/0x154
write_cache_pages+0x394/0x830
do_writepages+0x1f0/0x5b0
filemap_fdatawrite_wbc+0x170/0x25c
file_write_and_wait_range+0x140/0x190
ubifs_fsync+0xe8/0x290
vfs_fsync_range+0xc0/0x1e4
do_fsync+0x40/0x90
__arm64_sys_fsync+0x34/0x50
invoke_syscall.constprop.0+0xa8/0x260
do_el0_svc+0xc8/0x1f0
el0_svc+0x34/0x70
el0t_64_sync_handler+0x108/0x114
el0t_64_sync+0x1a4/0x1a8
Freed by task 403:
kasan_save_stack+0x38/0x70
kasan_set_track+0x28/0x40
kasan_set_free_info+0x28/0x4c
__kasan_slab_free+0xd4/0x13c
kfree+0xc4/0x3a0
tnc_delete+0x3f4/0xe40
ubifs_tnc_remove_range+0x368/0x73c
ubifs_tnc_remove_ino+0x29c/0x2e0
ubifs_jnl_delete_inode+0x150/0x260
ubifs_evict_inode+0x1d4/0x2e4
evict+0x1c8/0x450
iput+0x2a0/0x3c4
do_unlinkat+0x2cc/0x490
__arm64_sys_unlinkat+0x90/0x100
invoke_syscall.constprop.0+0xa8/0x260
do_el0_svc+0xc8/0x1f0
el0_svc+0x34/0x70
el0t_64_sync_handler+0x108/0x114
el0t_64_sync+0x1a4/0x1a8
The offending `memcpy()` in `ubifs_copy_hash()` has a use-after-free
when a node becomes root in TNC but still has a `cparent` to an already
freed node. More specifically, consider the following TNC:
zroot
/
/
zp1
/
/
zn
Inserting a new node `zn_new` with a key smaller then `zn` will trigger
a split in `tnc_insert()` if `zp1` is full:
zroot
/ \
/ \
zp1 zp2
/ \
/ \
zn_new zn
`zn->parent` has now been moved to `zp2`, *but* `zn->cparent` still
points to `zp1`.
Now, consider a removal of all the nodes _except_ `zn`. Just when
`tnc_delete()` is about to delete `zroot` and `zp2`:
zroot
\
\
zp2
\
\
zn
`zroot` and `zp2` get freed and the tree collapses:
zn
`zn` now becomes the new `zroot`.
`get_znodes_to_commit()` will now only find `zn`, the new `zroot`, and
`write_index()` will check its `znode->cparent` that wrongly points to
the already freed `zp1`. `ubifs_copy_hash()` thus gets wrongly called
with `znode->cparent->zbranch[znode->iip].hash` that triggers the
use-after-free!
Fix this by explicitly setting `znode->cparent` to `NULL` in
`get_znodes_to_commit()` for the root node. The search for the dirty
nodes is bottom-up in the tree. Thus, when `find_next_dirty(znode)`
returns NULL, the current `znode` _is_ the root node. Add an assert for
this.
Fixes: 16a26b20d2af ("ubifs: authentication: Add hashes to index nodes")
Tested-by: Waqar Hameed <waqar.hameed@axis.com>
Co-developed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Waqar Hameed <waqar.hameed@axis.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
